Prevent HTML5 video from being downloaded (right-click saved)?
How can I disable "Save Video As..." from a browser's right-click menu to prevent clients from downloading a video?
Are there more complete solutions that prevent the client from accessing a file path directly?
Answer
You can't. That's because that's what browsers were designed to do: Serve content. But you can make it harder to download.
First thing's first, you could disable the contextmenu event, aka "the right click". That would prevent your regular skiddie from blatantly ripping your video by right clicking and Save As. But then they could just disable JS and get around this or find the video source via the browser's debugger. Plus this is bad UX. There are lots of legitimate things in a context menu than just Save As.
You could also use custom video player libraries. Most of them implement video players that customize the context menu to your liking. So you don't get the default browser context menu. And if ever they do serve a menu item similar to Save As, you can disable it. But again, this is a JS workaround. Weaknesses are similar to the previous option.
Another way to do it is to serve the video using HTTP Live Streaming. What it essentially does is chop up the video into chunks and serve it one after the other. This is how most streaming sites serve video. So even if you manage to Save As, you only save a chunk, not the whole video. It would take a bit more effort to gather all the chunks and stitch them using some dedicated software.
Another technique is to paint <video> on <canvas>. In this technique, with a bit of JavaScript, what you see on the page is a <canvas> element rendering frames from a hidden <video>. And because it's a <canvas>, the context menu will use an <img>'s menu, not a <video>'s. You'll get a Save Image As instead of a Save Video As.
You could also use CSRF tokens to your advantage. You'd have your sever send down a token on the page. You then use that token to fetch your video. Your server checks to see if it's a valid token before it serves the video, or get an HTTP 401. The idea is that you can only ever get a video by having a token which you can only ever get if you came from the page, not directly visiting the video url.
At the end of the day, I'd just upload my video to a third-party video site, like YouTube or Vimeo. They have good video management tools, optimizes playback to the device, and they make efforts in preventing their videos from being ripped with zero effort on your end.